Hispanics are the largest and fastest growing ethnic group in the US with the rates of preterm birth increasing with acculturation. We have delineated a predictive pathway from acculturation through the endocrine and immune systems to decreased infant birth weight and decreased gestational age in Hispanic women. We are adding in the next steps for this competitive renewal of #7RoiNRooy89-O4 to (a) discover multidimensional direct and indirect effects of acculturation on gestational age and birth weight (b) elucidate periods (by serial measurements) for when the pathway occurs early in pregnancy, (c) identify the genetic predisposition (cytokine polymorphisms) for the immune component of the pathway, and (d) develop an allostatic load score and test its mediating effect between the path from acculturation to gestational age and birth weight. Aim l: To identify the effects of acculturation (using a multidimensional measurement) on emotional distress, health behaviors, and psychological protective factors affecting endocrine and immune responses which predict decreases in gestational age and birth weight. Aim 2: To identify whether antenatal endocrine and immune predictors of decreased gestational age and decreased birth weight are present in pregnant Hispanic women as early as 15-17 weeks. Aim 3: To identify inflammatory cytokine gene polymorphisms responsible for IL-1O, TNF-a, IL-6, and IL-i Ra production in pregnant women Hispanic women. Aim 4: To test a model linking components of acculturation with indicators of emotional distress, health behaviors, psychological protective factors and allostatic load (endocrine and immune factors) predicting decreased gestational age and decreased birth weight. The design is prospective, and observational, focusing on Hispanic women ages 14-45 with a single intrauterine pregnancy with a sample size of 500 women. Numerous self-report instruments will assess emotional distress and psychosocial protective factors. Acculturation will be measured by a multidimensional approach. We will measure nutrient intake by diet record and illicit drugs and smoking in the urine. We will measure in the blood numerous stress and reproductive hormones and inflammatory cytokines, and their gene polymorphisms. We will do a medical record review for maternal and infant outcomes. For aim i, we will use factor analysis of the domains of acculturation and Structural Equation Modeling (SEM) of the mediators of acculturation. For aim 2, we will use SEM for 15-17 weeks gestation and compare to the model at 22-24 weeks. We will analyze Aim 3 using X2, linear and logistic regression. For Aim 4, we will test the reliability and validity of the allostatic load (AL) score using internal consistency measures, and then factor analysis. Acculturation as a latent variable will be used with the AL score in SEM. We will add the mediating variables into the SEM and compare the model at 15-17 weeks and 22-24 weeks, concerned.